﻿#nullable disable
// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

using System.Diagnostics.CodeAnalysis;

namespace SwashbucklerDiary.Utilities
{
    internal partial class StaticContentProvider
	{
		private static readonly FileExtensionContentTypeProvider ContentTypeProvider = new();

		internal static string GetResponseContentTypeOrDefault(string path)
			=> ContentTypeProvider.TryGetContentType(path, out var matchedContentType)
			? matchedContentType
			: "application/octet-stream";

		internal static IDictionary<string, string> GetResponseHeaders(string contentType)
			=> new Dictionary<string, string>(StringComparer.Ordinal)
			{
				{ "Content-Type", contentType },
				{ "Cache-Control", "no-cache, max-age=0, must-revalidate, no-store" },
			};

		internal class FileExtensionContentTypeProvider
		{
			// Notes:
			// - This table was initially copied from IIS and has many legacy entries we will maintain for backwards compatibility.
			// - We only plan to add new entries where we expect them to be applicable to a majority of developers such as being
			// used in the project templates.
			#region Extension mapping table
			/// <summary>
			/// Creates a new provider with a set of default mappings.
			/// </summary>
			public FileExtensionContentTypeProvider()
				: this(new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
				{
				{ ".323", "text/h323" },
				{ ".3g2", "video/3gpp2" },
				{ ".3gp2", "video/3gpp2" },
				{ ".3gp", "video/3gpp" },
				{ ".3gpp", "video/3gpp" },
				{ ".aac", "audio/aac" },
				{ ".aaf", "application/octet-stream" },
				{ ".aca", "application/octet-stream" },
				{ ".accdb", "application/msaccess" },
				{ ".accde", "application/msaccess" },
				{ ".accdt", "application/msaccess" },
				{ ".acx", "application/internet-property-stream" },
				{ ".adt", "audio/vnd.dlna.adts" },
				{ ".adts", "audio/vnd.dlna.adts" },
				{ ".afm", "application/octet-stream" },
				{ ".ai", "application/postscript" },
				{ ".aif", "audio/x-aiff" },
				{ ".aifc", "audio/aiff" },
				{ ".aiff", "audio/aiff" },
				{ ".appcache", "text/cache-manifest" },
				{ ".application", "application/x-ms-application" },
				{ ".art", "image/x-jg" },
				{ ".asd", "application/octet-stream" },
				{ ".asf", "video/x-ms-asf" },
				{ ".asi", "application/octet-stream" },
				{ ".asm", "text/plain" },
				{ ".asr", "video/x-ms-asf" },
				{ ".asx", "video/x-ms-asf" },
				{ ".atom", "application/atom+xml" },
				{ ".au", "audio/basic" },
				{ ".avi", "video/x-msvideo" },
				{ ".axs", "application/olescript" },
				{ ".bas", "text/plain" },
				{ ".bcpio", "application/x-bcpio" },
				{ ".bin", "application/octet-stream" },
				{ ".bmp", "image/bmp" },
				{ ".c", "text/plain" },
				{ ".cab", "application/vnd.ms-cab-compressed" },
				{ ".calx", "application/vnd.ms-office.calx" },
				{ ".cat", "application/vnd.ms-pki.seccat" },
				{ ".cdf", "application/x-cdf" },
				{ ".chm", "application/octet-stream" },
				{ ".class", "application/x-java-applet" },
				{ ".clp", "application/x-msclip" },
				{ ".cmx", "image/x-cmx" },
				{ ".cnf", "text/plain" },
				{ ".cod", "image/cis-cod" },
				{ ".cpio", "application/x-cpio" },
				{ ".cpp", "text/plain" },
				{ ".crd", "application/x-mscardfile" },
				{ ".crl", "application/pkix-crl" },
				{ ".crt", "application/x-x509-ca-cert" },
				{ ".csh", "application/x-csh" },
				{ ".css", "text/css" },
				{ ".csv", "text/csv" }, // https://tools.ietf.org/html/rfc7111#section-5.1
                { ".cur", "application/octet-stream" },
				{ ".dcr", "application/x-director" },
				{ ".deploy", "application/octet-stream" },
				{ ".der", "application/x-x509-ca-cert" },
				{ ".dib", "image/bmp" },
				{ ".dir", "application/x-director" },
				{ ".disco", "text/xml" },
				{ ".dlm", "text/dlm" },
				{ ".doc", "application/msword" },
				{ ".docm", "application/vnd.ms-word.document.macroEnabled.12" },
				{ ".docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document" },
				{ ".dot", "application/msword" },
				{ ".dotm", "application/vnd.ms-word.template.macroEnabled.12" },
				{ ".dotx", "application/vnd.openxmlformats-officedocument.wordprocessingml.template" },
				{ ".dsp", "application/octet-stream" },
				{ ".dtd", "text/xml" },
				{ ".dvi", "application/x-dvi" },
				{ ".dvr-ms", "video/x-ms-dvr" },
				{ ".dwf", "drawing/x-dwf" },
				{ ".dwp", "application/octet-stream" },
				{ ".dxr", "application/x-director" },
				{ ".eml", "message/rfc822" },
				{ ".emz", "application/octet-stream" },
				{ ".eot", "application/vnd.ms-fontobject" },
				{ ".eps", "application/postscript" },
				{ ".etx", "text/x-setext" },
				{ ".evy", "application/envoy" },
				{ ".exe", "application/vnd.microsoft.portable-executable" }, // https://www.iana.org/assignments/media-types/application/vnd.microsoft.portable-executable
                { ".fdf", "application/vnd.fdf" },
				{ ".fif", "application/fractals" },
				{ ".fla", "application/octet-stream" },
				{ ".flr", "x-world/x-vrml" },
				{ ".flv", "video/x-flv" },
				{ ".gif", "image/gif" },
				{ ".gtar", "application/x-gtar" },
				{ ".gz", "application/x-gzip" },
				{ ".h", "text/plain" },
				{ ".hdf", "application/x-hdf" },
				{ ".hdml", "text/x-hdml" },
				{ ".hhc", "application/x-oleobject" },
				{ ".hhk", "application/octet-stream" },
				{ ".hhp", "application/octet-stream" },
				{ ".hlp", "application/winhlp" },
				{ ".hqx", "application/mac-binhex40" },
				{ ".hta", "application/hta" },
				{ ".htc", "text/x-component" },
				{ ".htm", "text/html" },
				{ ".html", "text/html" },
				{ ".htt", "text/webviewhtml" },
				{ ".hxt", "text/html" },
				{ ".ical", "text/calendar" },
				{ ".icalendar", "text/calendar" },
				{ ".ico", "image/x-icon" },
				{ ".ics", "text/calendar" },
				{ ".ief", "image/ief" },
				{ ".ifb", "text/calendar" },
				{ ".iii", "application/x-iphone" },
				{ ".inf", "application/octet-stream" },
				{ ".ins", "application/x-internet-signup" },
				{ ".isp", "application/x-internet-signup" },
				{ ".IVF", "video/x-ivf" },
				{ ".jar", "application/java-archive" },
				{ ".java", "application/octet-stream" },
				{ ".jck", "application/liquidmotion" },
				{ ".jcz", "application/liquidmotion" },
				{ ".jfif", "image/pjpeg" },
				{ ".jpb", "application/octet-stream" },
				{ ".jpe", "image/jpeg" },
				{ ".jpeg", "image/jpeg" },
				{ ".jpg", "image/jpeg" },
				{ ".js", "application/javascript" },
				{ ".json", "application/json" },
				{ ".jsx", "text/jscript" },
				{ ".latex", "application/x-latex" },
				{ ".lit", "application/x-ms-reader" },
				{ ".lpk", "application/octet-stream" },
				{ ".lsf", "video/x-la-asf" },
				{ ".lsx", "video/x-la-asf" },
				{ ".lzh", "application/octet-stream" },
				{ ".m13", "application/x-msmediaview" },
				{ ".m14", "application/x-msmediaview" },
				{ ".m1v", "video/mpeg" },
				{ ".m2ts", "video/vnd.dlna.mpeg-tts" },
				{ ".m3u", "audio/x-mpegurl" },
				{ ".m4a", "audio/mp4" },
				{ ".m4v", "video/mp4" },
				{ ".man", "application/x-troff-man" },
				{ ".manifest", "application/x-ms-manifest" },
				{ ".map", "text/plain" },
				{ ".markdown", "text/markdown" },
				{ ".md", "text/markdown" },
				{ ".mdb", "application/x-msaccess" },
				{ ".mdp", "application/octet-stream" },
				{ ".me", "application/x-troff-me" },
				{ ".mht", "message/rfc822" },
				{ ".mhtml", "message/rfc822" },
				{ ".mid", "audio/mid" },
				{ ".midi", "audio/mid" },
				{ ".mix", "application/octet-stream" },
				{ ".mmf", "application/x-smaf" },
				{ ".mno", "text/xml" },
				{ ".mny", "application/x-msmoney" },
				{ ".mov", "video/quicktime" },
				{ ".movie", "video/x-sgi-movie" },
				{ ".mp2", "video/mpeg" },
				{ ".mp3", "audio/mpeg" },
				{ ".mp4", "video/mp4" },
				{ ".mp4v", "video/mp4" },
				{ ".mpa", "video/mpeg" },
				{ ".mpe", "video/mpeg" },
				{ ".mpeg", "video/mpeg" },
				{ ".mpg", "video/mpeg" },
				{ ".mpp", "application/vnd.ms-project" },
				{ ".mpv2", "video/mpeg" },
				{ ".ms", "application/x-troff-ms" },
				{ ".msi", "application/octet-stream" },
				{ ".mso", "application/octet-stream" },
				{ ".mvb", "application/x-msmediaview" },
				{ ".mvc", "application/x-miva-compiled" },
				{ ".nc", "application/x-netcdf" },
				{ ".nsc", "video/x-ms-asf" },
				{ ".nws", "message/rfc822" },
				{ ".ocx", "application/octet-stream" },
				{ ".oda", "application/oda" },
				{ ".odc", "text/x-ms-odc" },
				{ ".ods", "application/oleobject" },
				{ ".oga", "audio/ogg" },
				{ ".ogg", "video/ogg" },
				{ ".ogv", "video/ogg" },
				{ ".ogx", "application/ogg" },
				{ ".one", "application/onenote" },
				{ ".onea", "application/onenote" },
				{ ".onetoc", "application/onenote" },
				{ ".onetoc2", "application/onenote" },
				{ ".onetmp", "application/onenote" },
				{ ".onepkg", "application/onenote" },
				{ ".osdx", "application/opensearchdescription+xml" },
				{ ".otf", "font/otf" },
				{ ".p10", "application/pkcs10" },
				{ ".p12", "application/x-pkcs12" },
				{ ".p7b", "application/x-pkcs7-certificates" },
				{ ".p7c", "application/pkcs7-mime" },
				{ ".p7m", "application/pkcs7-mime" },
				{ ".p7r", "application/x-pkcs7-certreqresp" },
				{ ".p7s", "application/pkcs7-signature" },
				{ ".pbm", "image/x-portable-bitmap" },
				{ ".pcx", "application/octet-stream" },
				{ ".pcz", "application/octet-stream" },
				{ ".pdf", "application/pdf" },
				{ ".pfb", "application/octet-stream" },
				{ ".pfm", "application/octet-stream" },
				{ ".pfx", "application/x-pkcs12" },
				{ ".pgm", "image/x-portable-graymap" },
				{ ".pko", "application/vnd.ms-pki.pko" },
				{ ".pma", "application/x-perfmon" },
				{ ".pmc", "application/x-perfmon" },
				{ ".pml", "application/x-perfmon" },
				{ ".pmr", "application/x-perfmon" },
				{ ".pmw", "application/x-perfmon" },
				{ ".png", "image/png" },
				{ ".pnm", "image/x-portable-anymap" },
				{ ".pnz", "image/png" },
				{ ".pot", "application/vnd.ms-powerpoint" },
				{ ".potm", "application/vnd.ms-powerpoint.template.macroEnabled.12" },
				{ ".potx", "application/vnd.openxmlformats-officedocument.presentationml.template" },
				{ ".ppam", "application/vnd.ms-powerpoint.addin.macroEnabled.12" },
				{ ".ppm", "image/x-portable-pixmap" },
				{ ".pps", "application/vnd.ms-powerpoint" },
				{ ".ppsm", "application/vnd.ms-powerpoint.slideshow.macroEnabled.12" },
				{ ".ppsx", "application/vnd.openxmlformats-officedocument.presentationml.slideshow" },
				{ ".ppt", "application/vnd.ms-powerpoint" },
				{ ".pptm", "application/vnd.ms-powerpoint.presentation.macroEnabled.12" },
				{ ".pptx", "application/vnd.openxmlformats-officedocument.presentationml.presentation" },
				{ ".prf", "application/pics-rules" },
				{ ".prm", "application/octet-stream" },
				{ ".prx", "application/octet-stream" },
				{ ".ps", "application/postscript" },
				{ ".psd", "application/octet-stream" },
				{ ".psm", "application/octet-stream" },
				{ ".psp", "application/octet-stream" },
				{ ".pub", "application/x-mspublisher" },
				{ ".qt", "video/quicktime" },
				{ ".qtl", "application/x-quicktimeplayer" },
				{ ".qxd", "application/octet-stream" },
				{ ".ra", "audio/x-pn-realaudio" },
				{ ".ram", "audio/x-pn-realaudio" },
				{ ".rar", "application/octet-stream" },
				{ ".ras", "image/x-cmu-raster" },
				{ ".rf", "image/vnd.rn-realflash" },
				{ ".rgb", "image/x-rgb" },
				{ ".rm", "application/vnd.rn-realmedia" },
				{ ".rmi", "audio/mid" },
				{ ".roff", "application/x-troff" },
				{ ".rpm", "audio/x-pn-realaudio-plugin" },
				{ ".rtf", "application/rtf" },
				{ ".rtx", "text/richtext" },
				{ ".scd", "application/x-msschedule" },
				{ ".sct", "text/scriptlet" },
				{ ".sea", "application/octet-stream" },
				{ ".setpay", "application/set-payment-initiation" },
				{ ".setreg", "application/set-registration-initiation" },
				{ ".sgml", "text/sgml" },
				{ ".sh", "application/x-sh" },
				{ ".shar", "application/x-shar" },
				{ ".sit", "application/x-stuffit" },
				{ ".sldm", "application/vnd.ms-powerpoint.slide.macroEnabled.12" },
				{ ".sldx", "application/vnd.openxmlformats-officedocument.presentationml.slide" },
				{ ".smd", "audio/x-smd" },
				{ ".smi", "application/octet-stream" },
				{ ".smx", "audio/x-smd" },
				{ ".smz", "audio/x-smd" },
				{ ".snd", "audio/basic" },
				{ ".snp", "application/octet-stream" },
				{ ".spc", "application/x-pkcs7-certificates" },
				{ ".spl", "application/futuresplash" },
				{ ".spx", "audio/ogg" },
				{ ".src", "application/x-wais-source" },
				{ ".ssm", "application/streamingmedia" },
				{ ".sst", "application/vnd.ms-pki.certstore" },
				{ ".stl", "application/vnd.ms-pki.stl" },
				{ ".sv4cpio", "application/x-sv4cpio" },
				{ ".sv4crc", "application/x-sv4crc" },
				{ ".svg", "image/svg+xml" },
				{ ".svgz", "image/svg+xml" },
				{ ".swf", "application/x-shockwave-flash" },
				{ ".t", "application/x-troff" },
				{ ".tar", "application/x-tar" },
				{ ".tcl", "application/x-tcl" },
				{ ".tex", "application/x-tex" },
				{ ".texi", "application/x-texinfo" },
				{ ".texinfo", "application/x-texinfo" },
				{ ".tgz", "application/x-compressed" },
				{ ".thmx", "application/vnd.ms-officetheme" },
				{ ".thn", "application/octet-stream" },
				{ ".tif", "image/tiff" },
				{ ".tiff", "image/tiff" },
				{ ".toc", "application/octet-stream" },
				{ ".tr", "application/x-troff" },
				{ ".trm", "application/x-msterminal" },
				{ ".ts", "video/vnd.dlna.mpeg-tts" },
				{ ".tsv", "text/tab-separated-values" },
				{ ".ttc", "application/x-font-ttf" },
				{ ".ttf", "application/x-font-ttf" },
				{ ".tts", "video/vnd.dlna.mpeg-tts" },
				{ ".txt", "text/plain" },
				{ ".u32", "application/octet-stream" },
				{ ".uls", "text/iuls" },
				{ ".ustar", "application/x-ustar" },
				{ ".vbs", "text/vbscript" },
				{ ".vcf", "text/x-vcard" },
				{ ".vcs", "text/plain" },
				{ ".vdx", "application/vnd.ms-visio.viewer" },
				{ ".vml", "text/xml" },
				{ ".vsd", "application/vnd.visio" },
				{ ".vss", "application/vnd.visio" },
				{ ".vst", "application/vnd.visio" },
				{ ".vsto", "application/x-ms-vsto" },
				{ ".vsw", "application/vnd.visio" },
				{ ".vsx", "application/vnd.visio" },
				{ ".vtx", "application/vnd.visio" },
				{ ".wasm", "application/wasm" },
				{ ".wav", "audio/wav" },
				{ ".wax", "audio/x-ms-wax" },
				{ ".wbmp", "image/vnd.wap.wbmp" },
				{ ".wcm", "application/vnd.ms-works" },
				{ ".wdb", "application/vnd.ms-works" },
				{ ".webm", "video/webm" },
				{ ".webmanifest", "application/manifest+json" }, // https://w3c.github.io/manifest/#media-type-registration
                { ".webp", "image/webp" },
				{ ".wks", "application/vnd.ms-works" },
				{ ".wm", "video/x-ms-wm" },
				{ ".wma", "audio/x-ms-wma" },
				{ ".wmd", "application/x-ms-wmd" },
				{ ".wmf", "application/x-msmetafile" },
				{ ".wml", "text/vnd.wap.wml" },
				{ ".wmlc", "application/vnd.wap.wmlc" },
				{ ".wmls", "text/vnd.wap.wmlscript" },
				{ ".wmlsc", "application/vnd.wap.wmlscriptc" },
				{ ".wmp", "video/x-ms-wmp" },
				{ ".wmv", "video/x-ms-wmv" },
				{ ".wmx", "video/x-ms-wmx" },
				{ ".wmz", "application/x-ms-wmz" },
				{ ".woff", "application/font-woff" }, // https://www.w3.org/TR/WOFF/#appendix-b
                { ".woff2", "font/woff2" }, // https://www.w3.org/TR/WOFF2/#IMT
                { ".wps", "application/vnd.ms-works" },
				{ ".wri", "application/x-mswrite" },
				{ ".wrl", "x-world/x-vrml" },
				{ ".wrz", "x-world/x-vrml" },
				{ ".wsdl", "text/xml" },
				{ ".wtv", "video/x-ms-wtv" },
				{ ".wvx", "video/x-ms-wvx" },
				{ ".x", "application/directx" },
				{ ".xaf", "x-world/x-vrml" },
				{ ".xaml", "application/xaml+xml" },
				{ ".xap", "application/x-silverlight-app" },
				{ ".xbap", "application/x-ms-xbap" },
				{ ".xbm", "image/x-xbitmap" },
				{ ".xdr", "text/plain" },
				{ ".xht", "application/xhtml+xml" },
				{ ".xhtml", "application/xhtml+xml" },
				{ ".xla", "application/vnd.ms-excel" },
				{ ".xlam", "application/vnd.ms-excel.addin.macroEnabled.12" },
				{ ".xlc", "application/vnd.ms-excel" },
				{ ".xlm", "application/vnd.ms-excel" },
				{ ".xls", "application/vnd.ms-excel" },
				{ ".xlsb", "application/vnd.ms-excel.sheet.binary.macroEnabled.12" },
				{ ".xlsm", "application/vnd.ms-excel.sheet.macroEnabled.12" },
				{ ".xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" },
				{ ".xlt", "application/vnd.ms-excel" },
				{ ".xltm", "application/vnd.ms-excel.template.macroEnabled.12" },
				{ ".xltx", "application/vnd.openxmlformats-officedocument.spreadsheetml.template" },
				{ ".xlw", "application/vnd.ms-excel" },
				{ ".xml", "text/xml" },
				{ ".xof", "x-world/x-vrml" },
				{ ".xpm", "image/x-xpixmap" },
				{ ".xps", "application/vnd.ms-xpsdocument" },
				{ ".xsd", "text/xml" },
				{ ".xsf", "text/xml" },
				{ ".xsl", "text/xml" },
				{ ".xslt", "text/xml" },
				{ ".xsn", "application/octet-stream" },
				{ ".xtp", "application/octet-stream" },
				{ ".xwd", "image/x-xwindowdump" },
				{ ".z", "application/x-compress" },
				{ ".zip", "application/x-zip-compressed" },
				})
			{
			}
			#endregion

			/// <summary>
			/// Creates a lookup engine using the provided mapping.
			/// It is recommended that the IDictionary instance use StringComparer.OrdinalIgnoreCase.
			/// </summary>
			/// <param name="mapping"></param>
			public FileExtensionContentTypeProvider(IDictionary<string, string> mapping)
			{
				if (mapping == null)
				{
					throw new ArgumentNullException(nameof(mapping));
				}
				Mappings = mapping;
			}

			/// <summary>
			/// The cross reference table of file extensions and content-types.
			/// </summary>
			public IDictionary<string, string> Mappings { get; private set; }

			/// <summary>
			/// Given a file path, determine the MIME type
			/// </summary>
			/// <param name="subpath">A file path</param>
			/// <param name="contentType">The resulting MIME type</param>
			/// <returns>True if MIME type could be determined</returns>
			public bool TryGetContentType(string subpath, [MaybeNullWhen(false)] out string contentType)
			{
				var extension = GetExtension(subpath);
				if (extension == null)
				{
					contentType = null;
					return false;
				}
				return Mappings.TryGetValue(extension, out contentType);
			}

			private static string GetExtension(string path)
			{
				// Don't use Path.GetExtension as that may throw an exception if there are
				// invalid characters in the path. Invalid characters should be handled
				// by the FileProviders

				if (string.IsNullOrWhiteSpace(path))
				{
					return null;
				}

				int index = path.LastIndexOf('.');
				if (index < 0)
				{
					return null;
				}

				return path.Substring(index);
			}
		}
	}
}
